1. Field of the Invention
The invention relates to overflow containers for accommodating overflow of radiators used with liquid cooled internal combustion engines, such as gasoline and Diesel engines.
2. Description of the Prior Art
Radiator overflow containers or tanks for some liquid cooled internal combustion engines operate at higher than atmospheric pressure. Such radiator overflow tanks are made of metal, with a radiator cap forming a gasketed metal-to-metal seal between a metal disk of the cap and a metallic portion of the overflow container. For economic reasons it would be desirable to be able to construct the body portion of a radiator overflow container or tank of plastic, with a metallic mouth or orifice for receiving a radiator cap embedded in a plastic wall of the tank. The differences in coefficients of thermal expansion between plastic and metal embedments therein, however, create a plastic-to-metal interface which is not liquid tight, especially when subjected to pressures above atmospheric pressure, over the normal operating temperature range of radiator overflow containers, the upper end of which may be as high as 240 degrees F.
It is the object of the present invention to provide a radiator overflow container suitable for use at higher than atmospheric pressure which has a plastic body portion and a metallic orifice for releasable engagement with a radiator cap, which will not leak at the plastic-to-metal interface between the plastic body portion and metallic ofifice over the normal operating temperature range of the liquid radiator coolant.